Accepted Answer

Thanks for the information and by the way your diagnosis seems quite accurate.

The first thing I'd like you to do is have the water tested for ammonia and nitrite levels.
My reasoning for this is that the majority of fish diseases stem from water quality problems and as you mentioned that you thoroughly cleaned the tank and have appeared to start with new water there is a high probability that there's ammonia and/or nitrite present.

Both ammonia and nitrite are deadly to fish and are caused by not having enough good bacteria to consume them. Listed below is a link to a page that will explain something called tank cycling.

Back to water testing. If you don't have a test kit available you can take a water sample to your local pet shop and they will usually test for free. Results should be ammonia and nitrite=-0-.
No other results are acceptable/good. The reason I am stressing the testing issue is because no treatment nor medication in the world will cure a fish if ammonia and nitrite are present in the water. Now if there is ammonia and/or nitrite present you should begin to do daily 20% water changes until ammonia and nitrites are eliminated.

Once ammonia/nitrite are eliminated you can then begin the recommended medication I will give you. Now if the water tests out -0- for ammonia and nitrite then no immediate water changes are necessary.

Septicemia is a bacterial infection of the blood, basically blood poisoning same as in humans.
The best medicine I know of to treat this type of disorder is called Triple Sulfa. Listed below is a link that will show you the product. Just follow the directions on the product label for use but please remember to test the water first as this medicine will prove useless if ammonia or nitrite are present.

I have also listed below a third link to an excellent goldfish site that will supply you with a lot of information about goldfish care. You can refer to it as needed as it is a very useful resource.

Please let me know if you have any questions on anything I've written and I'll be more than happy to elaborate.

http://www.thetropicaltank.co.uk/cycling.htm

http://www.drsfostersmith.com/product/prod_display.cfm?pcatid=4829&Ntt=septicemia&Ntk=All&Ntx=mode+matchallpartial&Np=1&pc=1&N=2004&Nty=1

http://www.goldfishinfo.com/

Expert:	TROPICAL FISH AFICIONADO
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Answered:	10/26/2007

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OVER 20 YEARS EXPERIENCE W/TROPICAL FISH---BREEDING, MAINTAINING, CURING